1289 


Issued  October  8,  1910. 


U.  S.  DEPARTMENT  OF  AGRICULTURE. 


FARMERS’  BULLETIN  419. 


Experiment  Station  Work, 

LIX. 

Compiled  from  the  Publications  of  the  Agricultural  Experiment  Stations. 


TILLAGE  v.  SOD  MULCH  IN  ORCHARDS.  BLACKLEG  OP  THE  IRISH  POTATO. 
EAR  CHARACTERS  OP  SEED  CORN.  PROGRESS  IN  HORSE  BREEDING. 

SEED  DISINFECTION.  SWEET  POTATOES. 


JULY,  1910. 


PREPARED  IN  THE  OFFICE  OF  EXPERIMENT  STATIONS. 

.  C.  TRUE,  Director. 


( 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE 

1910. 


THE  AGRICULTURAL  EXPERIMENT  STATIONS. 


Alabama — 

College  Station:  Auburn;  J.  F. 
Duggar.® 

Caneb rake  Station :  Uniontown;  F.  D. 
Stevens.® 

Tuskegee  Station :  Tuskegee  Institute; 
G.  W.  Carver. ® 

Alaska — Sitka:  C.  C.  Georgeson.6 
Arizona — Tucson:  R.  H.  Forbes. ® 
Arkansas— Fayetteville:  C.  F.  Adams.® 
California — Berkeley:  E.  J.  Wickson.® 
Colorado — Fort  Collins:  C.  P.  Gillette. ® 
Connecticut — 

•  State  Station:  New  Haven;  E.  II. 
Jenkins. « 

Storrs  Station:  Storrs;  L.  A.  Clinton. ® 
Delaware — Newark:  Harry  Hayward.0 
Florida — Gainesville:  P.  H.  Rolfs.0 
Georgia — Experiment:  Martin  V.  Cal¬ 
vin.0 

Guam — Island  of  Guam:  J.  B.  Thompson.  & 
Hawaii — 

Federal  Station:  Honolulu;  E.  V. 
Wilcox.  & 

Sugar  Planters’  Station:  Honolulu; 
C.  F.  Eckart.® 

Idaho — Moscow:  W.  L.  Carlyle.0 
Illinois — Urbana:  E.  Davenport.0 
Indiana — Lafayette:  A.  Goss.° 

Iowa — Ames:  C.  F.  Curtiss.® 

Kansas — Manhattan:  E.  H.  Webster.® 
Kentucky — Lexington:  M.  A.  Scovell.° 
Louisiana — 

State  Station:  Baton  Rouge. 

Sugar  Station:  Audubon  Park,  New 
Orleans. 

North  Louisiana  Station:  Calhoun. 
Rice  Experiment  Station:  Crowley ; 
W.  R.  Dodson  ( Baton  Rouge). ° 
Maine — Orono:  C.  D.  Woods.® 

Maryland — College  Park:  H.  J.  Patter¬ 
son.® 

Massachusetts — Amherst:  W.  P. 

Brooks.® 

Michigan — East  Lansing:  R.  S.  Shaw.® 
Minnesota — University  Farm ,  St.  Paul: 
A.  F.  Woods.® 

Mississippi — Agricultural  College:  J.  W. 
Fox.® 

Missouri — 

College  Station:  Columbia;  F.  B. 
Mumford.® 

a  Director.  b  Special  agent  i 

2 

410 


Missouri — Continued. 

Fruit  Station:  Mountain  Grove;  P. 
Evans.® 

Montana — Bozeman:  F.  B.  Linfield.® 
Nebraska — Lincoln:  E.  A.  Burnett.® 
Nevada — Reno:  J.  E.  Stubbs.® 

New  Hampshire — Durham:  J.  C.  Ken¬ 
dall.® 

New  Jersey — New  Brunswick:  E.  B. 
Voorhees.® 

New  Mexico — Agricultural  College:  L. 

Foster.® 

New  York — 

State  Station:  Geneva;  W.  H.  Jordan.® 
Cornell  Station:  Ithaca;  H.  J.  Web¬ 
ber.6 

North  Carolina — 

College  Station:  West  Raleigh;  C.  B. 
Williams.® 

State  Station:  Raleigh;  B.  W.  Kil¬ 
gore.® 

North  Dakota — Agricultural  College: 
J.  H.  Worst.® 

Ohio — Wooster:  C.  E.  Thorne.® 
Oklahoma — Stillwater:  B.  C.  Pittuck.6 
Oregon — Corvallis:  J.  Withycombe.® 
Pennsylvania — 

State  College:  T.  F.  Hunt.® 

State  College:  Institute  of  Animal 
Nutrition;  H.  P.  Armsby.® 

Porto  Rico — Mayaguez:  D.  W.  May.& 
Rhode  Island — Kingston:  H.  J. 
Wheeler.® 

South  Carolina — Clemson  College:  J.  N. 
Harper.® 

South  Dakota — Brookings:  J.  W.  Wil¬ 
son.® 

Tennessee — Knoxville:  H.  A.  Morgan.® 
Texas — College  Station:  H.  H.  Harring¬ 
ton.® 

Utah — Logan:  E.  D.  Ball.® 

Vermont — Burlington:  J.  L.  Hills.® 
Virginia — 

Blacksburg:  S.  W.  Fletcher.® 

Norfolk:  Truck  Station,  T.  C.  John¬ 
son.® 

Washington  —  Pullman:  R.  W. 
Thatcher.® 

West  Virginia — Morgantown:  J.  H. 
Stewart.® 

Wisconsin — Madison:  H.  L.  Russell.® 
Wyoming — Laramie:  H.  G.  Knight.® 
charge.  c  Acting  director. 


EXPERIMENT  STATION  WORK. 

Edited  by  W.  Ii.  Beal  and  the  Staff  of  the  Experiment  Station  Record. 


Experiment  Station  Work  is  a  subseries  of  brief  popular  bulletins  compiled 
from  the  published  reports  of  the  agricultural  experiment  stations  and  kindred 
institutions  in  this  and  other  countries.  The  chief  object  of  these  publications 
is  to  disseminate  throughout  the  country  information  regarding  experiments  at 
the  different  experiment  stations,  and  thus  to  acquaint  farmers  in  a  general 
way  with  the  progress  of  agricultural  investigation  on  its  practical  side.  The 
results  herein  reported  should  for  the  most  part  be  regarded  as  tentative  and 
suggestive  rather  than  conclusive.  Further  experiments  may  modify  them,  and 
experience  alone  can  show  how  far  they  will  be  useful  in  actual  practice.  The 
work  of  the  stations  must  not  be  depended  upon  to  produce  “rules  for  farm¬ 
ing.”  How  to  apply  the  results  of  experiments  to  his  own  conditions  will  ever 
remain  the  problem  of  the  individual  farmer. — A.  C.  True,  Director,  Office  of 
Experiment  Stations. 


CONTENTS  OF  NO.  FIX. 


Page. 


Tillage  versus  sod  mulch  in  apple  orchards .  5 

Ear  characters  of  seed  corn  in  relation  to  yield .  10 

Seed  disinfection  and  crop  production .  15 

Blackleg  of  the  Irish  potato .  18 

Progress  in  horse  breeding .  19 

Sweet  potatoes  and  their  preparation  for  the  table .  22 

Sweet-potato  pie .  23 

Sweet-potato  cobbler .  24 

Baked  sweet  potato  and  apples .  24 

419 


3 


ILLUSTRATIONS. 


Page. 

Fig.  1.  Long  and  short  ears  of  Learning  corn . . .  11 

2.  Cylindrical  and  tapering  ears  of  Learning  corn .  12 

3.  Filled  and  bare- tipped  ears  of  Clarage  corn .  13 

4.  One,  three,  and  five  plant  strains  of  Clarage  corn .  14 

4 

419 


EXPERIMENT  STATION  WORK. 


TILLAGE  VERSUS  SOD  MULCH  IN  APPLE  ORCHARDS.6 

Horticultural  investigators  quite  generally  agree  that  clean  tillage 
throughout  the  whole  season  is  not  good  orchard  practice,  since  con¬ 
stant  clean  tillage  not  only  depletes  the  humus  content  of  soils, thereby 
causing  them  to  pack  and  to  be  unable  to  retain  water  in  proper 
quantities,  but  it  is  also  responsible  for  considerable  soil  erosion  in 
hilly  sections.  Thus  the  term  “tillage”  as  applied  to  orchard  man¬ 
agement  has  come  to  mean  thorough  cultivation  of  the  orchard  during 
the  early  part  of  the  growing  season  followed  by  a  cover  crop  late  in 
the  summer,  which  is  in  turn  plowed  under  early  in  the  spring, 
thereby  adding  an  annual  supply  of  humus-forming  material  to  the 
soil. 

With  certain  modifications  to  meet  regional  requirements,  tillage 
as  above  defined  is  generally  recommended  as  the  best  orchard  prac¬ 
tice.  On  the  other  hand,  certain  orchardists,  notably  F.  P.  Vergon, 
of  Ohio,  and  Grant  Hitchings,  of  New  York,  have  been  highly  suc¬ 
cessful  in  growing  apples  under  the  so-called  sod  or  grass-mulch  sys¬ 
tems  of  soil  management.  These  men  have  many  supporters,  and 
considerable  discussion  has  arisen  as  to  the  relative  merits  of  the 
tillage  and  sod-mulch  methods  of  management.  It  is  true,  however, 
as  U.  P.  Hedrick,  -of  the  New  York  Geneva  Station,  says,  that  in  the 
discussion  which  has  been  going  on  men  for  the  most  part  have  been 
citing  particular  orchards,  isolated  cases  and  not  principles.  “The 
tillage  and  the  sod  methods  of  managing  orchards  are  so  radically 
different  that  they  can  not  be  equally  good.  *  *  *  It  seems  nec¬ 

essary  to  establish  by  means  of  experimental  evidence  principles  that 
will  apply  to  orchards  in  general.” 

At  least  three  of  the  state  stations  (Ohio,  New  York,  and  Pennsyl¬ 
vania)  are  conducting  long-continued  experiments  in  which  the  disputed 

aA  progress  record  of  experimental  inquiries,  published  without  assumption  of 
responsibility  by  the  Department  for  the  correctness  of  the  facts  and  conclusions 
reported  by  the  stations. 

b  Compiled  from  New  York  State  Sta.  Bui.  314;  Pennsylvania  Sta.  Bui.  91;  The 
study  of  a  mulched  orchard,  by  H.  W.  Collingwood,  Rural  New  Yorker,  68  (1909), 
Nos.  4017,  p.  921;  4018,  p.  941;  4019,  p.  962;  4020,  p.  983;  4022,  p.  1022;  4023,  p.  1047. 

419  5 


6 


EXPERIMENT  STATION  WORK,  LIX. 


systems  of  culture  are  being  studied  and  from  which  it  is  hoped  that 
certain  fundamental  principles  may  be  evolved  before  the  investiga¬ 
tions  are  completed.  The  average  results  secured  by  the  Ohio  Sta¬ 
tion  during  the  first  six  years  of  their  trials  have  been  reported  in  a 
previous  bulletin  of  this  series.0  Although  these  results  were  mark¬ 
edly  in  favor  of  the  sod-mulch  system  of  culture,  the  investigators, 
Green  and  Ballou,  considered  them  as  preliminary  only.  They  say 
“  the  results  of  investigations  *  *  *  were  secured  under  condi¬ 

tions  prevailing  at  the  experiment  station  orchards  alone,  and  it  is 
expressly  desired  that  this  record  of  results  be  accepted  as  suggestive 
rather  than  conclusive,  and  as  a  stimulus  to  individual  fruit  growers 
to  pursue  this  line  of  study  under  local  and  necessarily  widely  different 
conditions.” b 

In  the  attempt  to  find  out  whether  the  apple  thrives  best  under 
tillage  or  in  sod,  the  New  York  Station  is  conducting  two  experiments. 
In  a  bulletin  of  that  station  which  appeared  during  the  past  year, 
U.  P.  Hedrick  gave  a  preliminary  report  covering  a  period  of  five 
years  on  one  of  these  experiments.  The  other  experiment  has  not 
been  carried  far  enough  to  be  reported  on. 

The  experiment  under  consideration  was  begun  in  1903,  in  the 
orchard  of  Mr.  W.  D.  Auchter,  near  Rochester,  N.  Y.  The  orchard, 
which  consists  of  9£  acres  of  Baldwin  trees,  40  feet  apart  each  way, 
was  about  26  years  old,  when  the  experiment  was  started.  The  trees 
had  previously  been  under  tillage  with  an  annual  cover  crop.  There 
are  118  trees  in  the  sod  plat  and  121  in  the  tilled  plat.  The  orchard 
is  slightly  rolling  in  topography,  with  a  fertile  loam  to  a  depth  of  10 

a  sandy  subsoil.  Variations  in  soils  are  few  and 

slight. 

The  trees  in  the  two  plats  received  as  nearly  as  possible  identical 
treatment  as  to  pruning,  spraying,  fertilizing,  and  all  other  orchard 
operations,  excepting  the  system  of  culture,  which  was  as  follows: 

Sod  plat. — October  15,  1903,  8  quarts  each  of  orchard  grass  and  blue  grass  seed 
were  sown  per  acre,  from  which  a  fairly  good  stand  was  secured.  To  make  sure,  how¬ 
ever,  of  a  good  stand  of  grass,  a  second  seeding  of  1G  quarts  of  blue  grass,  8  quarts  of 
orchard  grass  and  3  quarts  of  timothy  seed  was  made  April  21,  1904.  During  the  first 
season  the  grass  flora  was  well  divided  between  the  above  three  grasses,  but  the  second 
year  the  orchard  grass  became  dominant  and  has  increased  in  quantity  until  now  [1909] 
the  plat  is  covered  with  an  orchard -grass  sod.  The  grass  was  mowed  on  the  following 
dates  during  the  five  years  of  the  experiment:  June  21  and  August  23,  1904;  June  12 
and  August  14,  1905;  June  18,  1906;  June  27,  1907;  May  27  and  July  4,  1908. 

The  grass,  if  allowed  to  stand  until  haying  time,  would  produce  2  tons  per  acre,  and 
when  cut  twice  the  crop  would  exceed  this  amount.  *  *  *  It  was  in  all  cases 
allowed  to  remain  where  it  fell  from  the  mower,  as  the  roots  of  the  trees  spread  over 
the  entire  orchard  area  and  there  was  therefore  need  to  mulch  the  whole  area. 


inches  underlain  by 


aU.  S.  Dept.  Agr.,  Farmers’  Bui.  267,  p.  23. 
419 


b  Ohio  Sta.  Bui.  171,  p.  208. 


EXPERIMENT  STATION  WORK,  LIX. 


7 


Tilled  plat. — The  following  is  a  memorandum  of  the  treatment  or  the  tilled  plat: 

1904.  Plat  plowed  June  7-11;  ground  harrowed  June  13,  June  20,  July  19,  July  29. 
Cover  crop  of  mammoth  clover  sown  July  30  and  the  seed  harrowed  in  with  a  weeder. 

1905.  Plat  plowed  May  30;  rolled  June  5;  harrowed  June  13;  June  26,  July  7,  July  22, 
August  2.  Mammoth  clover  sown  August  3  and  the  seed  covered  with  a  weeder, 
followed  by  a  roller. 

1906.  Plat  plowed  June  4-6;  rolled  and  harrowed  June  7 ;  harrowed  June  22,  July  19, 
August  2.  A  cover  crop  of  oats  was  sown  August  2  and  harrowed  in  the  next  day. 

1907.  Plat  plowed  May  27-29;  land  harrowed  May  31,  June  28,  July  17,  July  27, 
August  5.  A  cover  crop  of  mammoth-  clover  was  sown  August  6  and  covered  with  a 
weeder. 

1908.  Plat  plowed  May  23-26;  land  harrowed  May  27,  June  4,  12,  23,  and  July  31. 
A  cover  crop  of  oats  was  sown  July  31  and  harrowed  in  the  following  day  with  a  weeder. 

The  relative  merits  of  the  two  methods  were  gauged  by  all  impor¬ 
tant  characters  of  fruit  and  tree.  Professor  Hedrick  summarizes 
the  results  for  the  five  years  as  follows: 

The  average  yield  on  the  sod  plat  for  the  five  years  was  72.9  barrels  per  acre;  for 
the  tilled  plat,  109.2  barrels;  difference  in  favor  of  tilled  plat,  36.3  barrels. 

Estimates  made  at  blooming  and  fruiting  time  showed  a  far  greater  number  of  fruits 
on  the  tilled  trees.  Actual  count  showed  434  apples  per  barrel  on  the  sod  land  weigh¬ 
ing  5.01  ounces  each,  and  309  apples  per  barrel  on  the  tilled  plat  weighing  7.04  ounces 
each. 

The  fruit  from  the  sod-mulch  plat  is  much  more  highly  colored  than  that  from  the 
tilled  plat. 

The  fruit  on  the  sod-mulch  plat  matures  from  one  to  three  weeks  earlier  than  that 
on  the  tilled  plat. 

In  common  storage,  fruit  from  the  tilled  plat  keeps  four  weeks  longer  than  that 
from  the  sod  plat.  In  cold  storage,  the  keeping  quality  of  the  two  fruits  is  the  same. 

The  tilled  fruit  is  decidedly  better  in  quality,  being  crisper,  more  juicy,  and  of 
better  flavor. 

The  advantage  of  tillage  over  the  sod-mulch  in  the  matter  of  uniformity  of  trees 
and  crops  is  marked.  The  trees  in  sod  showed  abnormalities  in  foliage,  branches, 
roots  and  particularly  in  fruit-bearing  and  in  fruit  characters. 

The  average  gain  in  diameter  of  trunk  for  the  trees  in  sod  for  the  five  years  was  1.1 
inches;  for  the  trees  under  tillage,  2.1  inches;  gain  in  favor  of  tillage,  1  inch. 

The  dark,  rich  green  color  of  the  foliage  of  the  tilled  trees  indicated  that  the  tilled 
trees  were  in  the  best  of  health.  On  the  other  hand  the  yellow  color  of  the  leaves 
of  the  sod  trees  told  at  once  that  something  was  amiss. 

It  needed  only  a  glance  in  the  orchard  to  see  that  the  leaves  of  the  tilled  trees  were 
much  larger  and  much  more  numerous  and  that  therefore  the  total  leaf  area  was  much 
greater. 

Leaves  from  sodded  trees  and  the  same  number  (2,400)  from  tilled  trees  were 
weighed  and  gave  8.7  grams  as  the  average  weight  per  leaf  for  the  sodded  trees  and 
11.5  grams  for  the  tilled  trees. 

The  leaves  of  the  tilled  trees  came  out  three  or  four  days  earlier  and  remained  on 
the  trees  a  week  or  ten  days  later  than  on  the  sodded  trees. 

The  average  annual  growth  of  branches  for  the  sodded  trees  was  1.9  inches;  for  the 

* 

tilled  trees,  4.4  inches.  The  average  number  of  laterals  per  branch  on  the  sodded 
trees  was  3.4;  on  the  tilled  trees,  6.7. 

During  the  dormant  season  there  was  a  striking  difference  in  the  appearance  of  the 
new  'frood  in  the  two  plats.  The  new  wood  on  the  tilled  trees  was  plumper  and 
brighter  in  color,  indicating  better  health. 

419 


8  EXPERIMENT  STATION  WORK,  LIX. 

The  amount  of  dead  wood  in  the  sod-mulch  trees  was  much  greater  than  in  the  tilled 
trees. 

The  roots  of  the  trees  in  the  sod-mulch  plat  came  to  the  very  surface  of  the  ground. 
How  much  these  trees  suffered  by  the  destruction  of  roots  in  the  heat  and  drought 
of  summer  or  the  cold  of  winter  can  not  be  said.  In  the  tilled  land  the  roots  were 
found  in  greatest  abundance  at  a  depth  of  from  3  to  10  inches. 

The  circumference  of  the  root  systems  in  the  tilled  trees  is  approximately  circular, 
but  the  circumference  of  the  roots  of  the  trees  in  sod  is  very  irregular,  indicating  a 
reaching  out  of  a  part  of  the  roots  in  response  to  a  demand  for  more  moisture,  food, 
or  air,  or  to  escape  some  evil  effect  of  the  grass  roots. 

A  fair  way  of  comparing  the  quantity  of  the  living  roots  of  the  trees  in  the  two  plats 
could  not  be  found. 

The  trees  in  the  outside  rows  of  the  sod  plat,  where  the  roots  could  penetrate  into 
the  tilled  land,  without  exception  showed  better  health  and  greater  productivity 
than  the  trees  in  the  inner  rows. 

The  average  cost  per  acre  for  the  two  methods  of  management,  not  including  har¬ 
vesting,  was  $17.92  for  the  sod,  and  $24.47  for  tillage,  giving  a  difference  of  $6.55  in 
favor  of  the  sod.  The  average  net  income  per  acre  for  the  sod  plat  was  $71.52;  for 
the  tilled  plat,  $110.43,  a  difference  of  $38.91  in  favor  of  tillage,  an  increase  of  54  per 
cent  for  tillage  over  the  sod-mulch  method  of  management. 

Upon  analyzing  the  data  secured  in  the  work,  Professor  Hedrick 
finds  that  the  tilled  plat  was  superior  to  the  sod  plat  for  a  number 
of  reasons,  chief  of  which  is  that  the  tilled  soil  contained  more  mois¬ 
ture  and  consequently  furnished  a  better  medium  for  rendering  food 
available  to  the  tree.  The  tilled  soil  also  contained  more  humus 
and  was  from  1  to  2  degrees  warmer  than  the  sod  land.  It  is  also 
pointed  out  that  tilled  soils  are  better  aerated  than  sodded  land  and 
contain  a  greater  number  of  beneficial  micro-organisms. 

As  to  the  positive  injurious  effects  of  grass  on  apples,  Professor 
Hedrick  calls  attention  to  the  possible  toxic  effect  of  the  grass  roots 
but  in  lieu  of  further  evidence  along  this  line  he  prefers  to  attribute 
the  injurious  action  to  disturbances  of  plant  nutrition.  Analyses 
made  in  1908  show  that  the  soils  in  the  two  plats  varied  only  slightly 
as  to  the  amounts  of  the  several  plant  foods. 

If  lack  of  food  is  the  cause  of  the  deleterious  effect  of  the  sod  on  the  trees  it  is  starva¬ 
tion  in  the  midst  of  abundance.  The  food  is  in  the  soil,  but  because  of  a  lack  of  water 
to  bring  it  into  solution,  or  because  the  soluble  fertility  is  monopolized  by  the  grass, 
the  trees  do  not  get  it.  The  fact  that  the  grass  does  not  seemingly  suffer  suggests 
that  the  grass  roots  surround  the  tree  roots  and  have  the  first  opportunity  to  take 
moisture  and  food  and  leave  but  little  for  the  rootlets  of  the  trees. 

The  last  consideration  suggests  that  in  deep,  fertile  soils,  where  the  tree  roots  may 
go  down  and  escape  the  grass  roots,  competition  between  the  two  plants  may  be  less 
strenuous  and  the  effects  of  the  grass  on  the  apple  therefore  less  harmful  than  in  the 
comparatively  shallow  soil  of  the  Auchter  orchard.  The  data,  secured  from  a  num¬ 
ber  of  orchardists,  show  that  the  orchard  soils  of  New  York  are  shallow.  In  333 
orchards  out  of  528  in  this  State  the  top-soil  is  not  over  12  inches  deep.  The  average 
depth  of  the  top-soil  in  the  Auchter  orchard  is,  as  we  have  seen,  from  9  to  12  inches. 
Since  the  rooting  habits  of  trees  are  very  different,  sod  may  be  more  harmful  to  some 
varieties  than  to  others.  *  *  *  The  experiment  does  not  show  that  apples  can 
419 


EXPERIMENT  STATION  WORK,  LIX. 


9 


not  be  grown  in  sod.  There  are  many  orchards  in  New  York  which  would  prove 
the  contrary.  It  suggests,  however,  that  apples  thrive  in  sod,  not  because  of  the 
sod,  but  in  spite  of  it.  The  fact  that  there  are  many  thrifty  orchards  in  sod  in  New 
York  is  not  proof  that  these  orchards  would  not  do  better  under  tillage. 

In  considering  the  two  methods  of  management,  of  all  the  factors  affecting  the 
growth  of  trees  in  this  experiment,  conservation  of  moisture  should  receive  first  atten¬ 
tion  from  the  apple  grower.  This  statement  is  affirmed  not  only  by  the  results  in  the 
Auchter  orchard  but  in  practice  the  world  over.  The  climate  of  Europe  is  moist; 
sod  orchards  are  the  rule  there.  Near  the  Atlantic  seaboard  in  America,  as  in  New 
England,  where  the  rainfall  is  comparatively  high,  thrifty  orchards  are  found  in  sod. 
In  the  western  fruit  regions,  where  irrigation  is  practiced,  sod  orchards  are  hardly 
to  be  found;  water  is  purchased  and  must  be  conserved.  In  irrigated  lands  tillage  is 
found  to  be  the  best  means  of  moisture  conservation.  Moisture  is  by  no  means  the 
only  factor  to  be  considered  in  the  controversy  over  the  sod  and  tillage  methods  of 
management,  but  it  appears  to  be  the  chief  one. 

The  experiment  being  conducted  by  J.  P.  Stewart  at  the  Pennsyl¬ 
vania  Station  was  not  started  until  1907  and  no  definite  results  can 
be  expected  for  some  time.  As  determined  by  the  yields  for  two 
years,  however,  the  results  indicate  that  a  sod-mulch  treatment, 
which  in  this  case  consists  of  an  annual  mulch  of  straw  at  the  rate  of 
3  tons  per  acre  in  addition  to  the  grass  left  in  the  orchard,  uis  of  value 
in  developing  and  establishing  the  bearing  habit  in  orchards  which 
have  reached  the  bearing  size  and  a ge,”  and  that  with  mature 
orchards  tillage  is  to  be  preferred. 

The  other  experiment,  which  the  New  York  Station  is  conducting, 
is  located  on  the  Hitchings  farm,  where  the  sod-mulch  system  has 
been  so  successfully  employed.  This  experiment  should  be  of  par¬ 
ticular  value  in  showing  why  Mr.  Hitchings  has  so  successfully  grown 
his  orchards  in  sod. 

In  the  light  of  present  knowledge,  however,  it  would  seem  that  a 
successfully  grown  sod-mulcli  orchard  is  the  exception.  To  those 
who  believe  their  soil  is  sufficiently  moist  and  deep  to  grow  their 
trees  in  sod,  the  following  remarks  of  H.  W.  Collingwood,  who  recently 
conducted  a  critical  study  of  the  Hitchings  orchards,  should  prove 
of  some  value.® 

I  can  see  only  one  reason  why  Mr.  Hitchings  should  want  to  plow  in  order  to  improve 
the  trees.  They  are  satisfactory  in  their  performance  and  promise  as  they  stand. 
The  most  serious  objection  I  have  found  to  this  sod  culture  is  the  danger  from  fire. 
Should  fire  start  on  a  dry,  windy  day,  say  in  spring,  before  the  new  growth  starts,  the 
work  of  years  would  be  quickly  wiped  out.  I  know  this,  because  fire  swept  through 
my  own  orchard  and  ruined  several  hundred  young  trees.  That  is  the  weak  point  in 
a  mulched  orchard  and  it  is  a  serious  problem.  Near  a  railroad  or  where  careless 
hunters  roam  a  mulched  orchard  without  fire  protection  for  the  trees  is  always  in 
danger  when  the  grass  is  dry.  We  plow  a  wide  strip  around  the  orchard  to  keep  out 
running  fires,  and  in  some  exposed  places  plow  strips  along  the  rows.  *  *  *  The 
fire  peril  is  the  most  serious  objection  to  mulching  that  I  have  found.  *  *  *  Of 

one  thing  I  am  sure — any  man  who  thinks  he  can  produce  another  Hitchings  orchard 


“Rural  New  Yorker,  68  (1909),  No.  4023,  p.  1047. 
57508°— Bull.  419—10 - 2 


10 


EXPERIMENT  STATION  WORK,  LIX. 


without  leaving  everything  that  grows  except  the  apples,  and  hauling  in  other  mulch¬ 
ing  material  also,  will  fail  eight  times  in  ten. 

EAR  CHARACTERS  OF  SEED  CORN  IN  RELATION  TO  YIELD.® 

The  main  purpose  of  seed  corn  selection  is  to  increase  the  yield 
of  shelled  corn  per  acre.6  It  is  of  first  importance  then  to  know 
what  ascertainable  characters  indicate  the  most  productive  ear. 
The  average  man  can  not  select  his  seed  corn  with  the  aid  of  a  chem¬ 
ical  laboratory  and  does  not  know  its  pedigree,  although  he  may  keep 
his  own  breeding  plats  and  increase  fields.  He  should  see  the  mother 
plants  and  the  surroundings  from  which  his  seed  ears  have  come. 
Field  selection  enables  him  to  do  this,  but  its  complete  success 
demands  knowledge  of  the  conditions  of  growth  most  likely  to  give 
seed  vigor  and  prolificacy  and  a  keen  appreciation  of  the  ear  char¬ 
acters  that  indicate  seed  of  great  yielding  power.  Which  will  pro¬ 
duce  the  more  corn  per  acre,  the  long  ear  or  the  short  ear,  the  light 
ear  or  the  heavy  ear,  the  one  with  the  bare  tip  or  with  the  well-filled 
tip,  the  one  with  a  high  or  low  shelling  percentage,  with  a  tapering 
or  cylindrical  shape,  with  rough  or  smooth  indentation  ?  Since  few 
ears  are  strong  in  every  point,  which  is  to  be  the  most  sought  for,  the 
good  butt  or  a  good  tip,  a  good  kernel  or  a  symmetrical  ear  ?  These 
and  similar  questions  the  score  card  undertakes  to  answer,  but  it 
indicates  what  is  good  corn  rather  than  what  ears  will  produce 
greatest  yield  when  planted.  Its  standards  are  those  of  the  market 
rather  than  those  of  the  farm,  although  an  effort  is  made  to  avoid 
this  by  assigning  great  weight  to  points  indicating  high  germinating 
power.  The  ear  having  the  greatest  weight,  symmetry,  and  shelling 
percentage  will  not  necessarily  produce  the  highest  yield  when 
planted.  Score  card  standards  and  values  are  only  estimates  at 
best.  An  attempt  is  being  made  to  answer  the  same  questions  by 
careful  trials  at  the  Ohio  Agricultural  Experiment  Station.  The 
relation  of  shape  of  ear,  filling  of  tip,  indentation  of  the  kernel, 
weight  of  ear,  and  environment  of  the  parent  plants  to  the  yielding 
power  of  seed  corn  are  being  tested  in  experiments  that  have  already 
been  conducted  for  four  or  five  years. 

During  the  period  1905-1909,  long  ears  produced  higher  yields  than 
short  ears  in  21  out  of  22  tests  (see  fig.  1),  the  average  difference  in 
yield  being  3.97  bushels  per  acre.  In  1909,  5  varieties  were  tested 
and  the  long  ears  invariably  led  in  yield  by  amounts  ranging  from 
2.53  to  6.77  bushels  per  acre  for  the  different  varieties,  the  average 
difference  being  5.18  bushels  per  acre  and  the  average  difference  in 

a Compiled  from  Ohio  Sta.  Bui.  212;  Circ.  71. 

b  Various  phases  of  corn  breeding  have  been  fully  dealt  with  in  previous  articles. 
See  U.  S.  Dept.  Agr.,  Farmers’  Buis.  210,  p.  11;  267,  p.  5;  366,  p.  10. 

419 


EXPERIMENT  STATION  WORK,  LIX. 


11 


length  of  seed  ears  2.2  inches.  The  greatest  increase  in  yield  is 
observed  in  the  group  where  the  greatest  difference  of  length  of  the 
long  and  short  ears  is  found,  while  the  least  increase  in  yield  comes 
in  the  group  where  there  is  the  least  difference  in  length.  The  low- 
yielding  short  ears  invariably  exceeded  the  long  ears  in  circumference, 
so  that  it  would  seem  impossible  to  increase  the  yield  of  the  short  ears 
by  increasing  their  circumference  to  balance  their  lack  in  weight,  if 
weight  should  prove  to  be  an  important  factor  in  increasing  the  yield. 
In  case  of  two  of  the  varieties  tested  the  average  weight  of  the  long 
ears  planted  was  exactly  equal.  The  advantage  in  yield  due  to 
superior  length  was  4.24  bushels  per  acre  greater  in  case  of  the  variety 
having  the  greater  difference  in  length  between  its  long  and  short  ears. 
Although  the  longer  ears  outyield  the  shorter  there  is  no  evidence  that 
selection  for  extremely  long  ears  increases  the  yield  above  those  of 
medium  length.  The  difference  in  yield  seems  to  result  from  a  less- 


Fig.  1. — Long  and  short  ears  of  Learning  corn. 


ened  yield  due  to  selection  for  short  ears  rather  than  to  an  increased 
yield  from  the  selection  for  long  ears. 

In  the  study  of  the  relation  of  shape  of  ear  to  yield,  18  tests  have 
been  made,  and  during  the  first  and  third  years  the  cylindrical  ears 
led  slightly  in  yield,  while  during  the  second  and  fourth  years  the 
tapering  ears  led.  The  combined  average  shows  a  difference  of  0.87 
bushel  per  acre  in  favor  of  the  tapering  ears.  In  1909  each  of  4 
varieties  tested  showed  a  gain  for  cylindrical  ears,  but  Reid  Yellow 
Dent  was  the  only  variety  in  which  the  variation  in  yield  was  of  any 
importance,  the  average  difference  being  1.08  bushels.  (See  fig.  2.) 

From  ears  of  Clarage  corn  having  f  to  1J  inches  of  bare  cob  at  the 
tip  and  others  completely  filled  (see  fig.  3),  it  appeared  that  while 
the  bare-tipped  ears  yielded  0.42  bushel  per  acre  more  than  those 
with  well-filled  tips  the  first  year,  continued  selection  of  well-tipped 
ears  from  well-tipped  parents  showed  an  advantage  of  1.45  bushels 

419 


12 


EXPERIMENT  STATION  WORK,  LIX. 


per  acre  in  the  second  year  and  of  2.19  bushels  per  acre  in  the  third  year 
for  corn  grown  from  well-tipped  ears.  In  the  three  years  of  the  test  3.7 
per  cent  of  the  ears  produced  from  bare-tipped  seed  ears  had  com¬ 
pletely  filled  tips,  as  compared  with  20  per  cent  from  the  filled- 
tipped  seed  ears.  The  average  length  per  ear  of  bare  tips  in  the 
harvest  from  the  bare-tipped  seed  ears  was  1.03  inches  as  compared 
with  0.53  for  the  harvest  from  the  filled-tipped  seed  ears.  The  crop 
from  the  bare-tipped  ears  has  an  advantage  in  length  of  ears  of  0.18 
inch,  but  if  the  bare  portion  of  the  ear  is  omitted  from  consideration 
the  progeny  of  the  well-tipped  ears  had  an  advantage  of  0.32  inch  in 
length.  The  continued  selection  of  ears  having  f  to  11  inches  of  bare 
cob  at  the  tip  tends  to  reproduce  ears  of  this  character  and  to  reduce 
the  percentage  of  ears  having  filled  tips  and  to  decrease  the  yield. 

During  five  years  ear-row  tests  of  seed  ears  of  the  crease-dented 
type  produced  an  average  yield  of  2.84  bushels  per  acre  greater  than 


> ****>> •  «  *! 


Fig.  2. — Cylindrical  and  tapering  ears  of  Learning  corn,  compared  with  a  10-inch  ruler. 

that  produced  by  rough-dented  ears.  During  one  year  of  plat  work, 
the  rough-dented  ears  showed  an  advantage  of  1  bushel  and  during 
the  second  year  the  crease-dented  ears  had  an  advantage  of  2.17 
bushels  per  acre  in  yield.  The  crease-dented  ears  used  during  the 
last  year  in  plat  work  averaged  1.2  ounces  lighter,  0.2  inch  shorter, 
0.5  inch  less  in  circumference,  and  3.5  less  in  shelling  percentage. 
While  some  of  these  characters  taken  singly  tend  to  produce  an 
increase  in  yield  they  were  insufficient  to  overcome  the  differences  in 
indentation. 

The  heavier  seed  ears  may  usually  lie  depended  upon  to  give  higher 
yields.  Total  weight  of  ear  appears  to  be  a  better  guide  to  pro¬ 
ductive  power  than  weight  of  shelled  corn,  provided  this  weight  is 
due  to  a  reasonable  length,  circumference,  and  amount  and  density 

419 


EXPERIMENT  STATION  WORK,  LIX. 


13 


of  grain  and  cob,  and  does  not  occur  in  a  large  immature  ear.  During 
three  years7  ear-row  tests,  ears  having  an  average  advantage  of  2.06 
ounces  in  weight  produced  yields  5.9  bushels  per  acre  greater  than 
did  the  lighter  ears.  Of  400  ears  tested,  the  heaviest  40  per  cent 
exceeded  in  average  weight  the  lightest  40  per  cent  by  2.46  ounces 
per  ear  and  produced  a  yield  greater  by  2.08  bushels  per  acre.  In 
plat  tests,  50  heavy  seed  ears  yielded  at  the  rate  of  0.63  bushel  per 
acre  more  during  the  first  year  and  3.23  during  the  second  year  than 
did  the  lighter  ears.  Of  the  same  400  seed  ears,  the  40  per  cent 
having  the  highest  shelling  percentage  produced  average  yields  1.2 
bushels  lower  than  the  40  per  cent  having  the  lowest  shelling  percent¬ 
age.  The  shelling  percentage  of  the  harvest  was  4.2  per  cent  in  favor 
of  that  from  the  seed  ears  having  the  higher  shelling  percentage. 
Among  200  ears  the  20  having  the  lowest  shelling  percentage  ex- 


Fig.  3. — Filled  and  bare-tipped  ears  of  Clarage  corn. 

celled  the  20  having  the  highest  by  6.42  in  shelling  percentage  and  by 
3.57  bushels  per  acre  in  yield. 

In  the  selection  of  seed  the  environment  of  the  mother  plants 
should  be  considered.  As  ordinarily  selected  from  the  shock,  wagon, 
or  crib,  most  of  the  ears  are  probably  excellent  because  they  grew 
under  favorable  surroundings.  Their  superiority  is  probably  due  to 
the  fact  that  the  mother  plant  received  the  food,  sunlight,  and 
moisture  intended  for  several  plants.  Field  selection  will  avoid  a 
part  of  this  difficulty,  as  it  is  well  known  that  seed  produced  under 
such  favorable  circumstances  is  less  vigorous  under  unfavorable  con¬ 
ditions.  Seed  selected  from  the  plant  has  been  found  to  yield  an  aver¬ 
age  of  3.23  bushels  per  acre  more  than  that  selected, from  the  wagon 
but  grown  in  the  same  field.  The  ears  selected  from  the  wagon  were 
superior  in  size  and  general  appearance  but  the  environment  in  which 
thev  were  produced  was  of  course  not  definitelv  known.  The  time  of 
maturity  of  the  ear,  number  of  ears  per  plant,  the  fertility  of  the  soil, 

419 


14 


EXPERIMENT  STATION  WORK,  LIX. 


the  proximity  of  barren  stalks,  and  the  number  of  plants  in  the  hill 
should  be  considered,  as  should  also  the  vigor  of  the  plant  and  its 
abilty  to  stand  upright.  This  ability  does  not  result  entirely  from  a 
lighter  load,  for  an  ear  which  yielded  75.6  bushels  per  acre  produced 
plants  only  44  per  cent  of  which  stood  upright,  while  another  ear 
yielding  114.7  bushels  per  acre  produced  plants  every  one  of  which 
remained  standing.  Seed  corn  from  a  highly  manured  plat  in  1907 
produced  0.98  bushel  less  corn  per  acre  than  did  that  from  a  plat 
which  had  remained  unfertilized  for  sixteen  years,  and  in  1908,  2.32 
bushels  more,  while  in  1909,  the  seed  from  the  unfertilized  plat  led  in 
yield  by  3.8  bushels.  Ears  selected  from  stalks  grown  in  normal 
stand  produced  in  a  four  years’  test  an  average  of  2.36  bushels  more 


Fig.  4.— One,  three,  and  five  plant  strains  of  Clarage  corn.  One  plant  strain  at  top. 


per  acre  than  did  ears  selected  from  the  wagon  and  without  any 
knowledge  of  the  stand.  Seed  selected  from  plats  planted  at  rates 
of  1,  3,  and  5  plants  per  hill  produced  yields  of  91.49,  91.74  (see  fig. 
4),  and  92.58  bushels  per  acre,  respectively.  While  these  differences 
are  slight  they  indicate  that  seed  ears  inferior  in  size  and  appearance 
because  of  environment  may  be  superior  in  hereditary  value. 

Undue  dependence  is  often  placed  upon  the  germination  test 
which  will  at  best  indicate  only  which  ears  will  grow  and  which 
will  not.  From  600  ears  germinated  under  1  inch  of  soil  those 
first  up  produced  an  average  yield  of  2.84  bushels  less  than  those 
which  came  up  last.  They  probably  contained  a  larger  proportion 

419 


EXPERIMENT  STATION  WORK,  LIX. 


15 


of  white  starch,  which  absorbed  water  more  rapidly,  and  so  caused 
more  rapid  germination.  The  40  per  cent  of  the  ears  showing  the 
best  germination  test  produced  an  average  yield  of  0.68  bushel  per 
acre  greater  than  the  40  per  cent  showing  the  poorest  germination, 
but  in  this  test  only  those  ears  were  considered  of  which  every  kernel 
planted  grew.  A  new  variety  should  not  be  discarded  because  it 
fails  to  excel  native  varieties  during  the  first  year  of  its  test  in  the 
new  locality.  A  longer  period  of  continuous  selection  is  necessary 
to  determine  its  real  value  when  fully  adjusted  to  local  conditions 
and  to  eliminate  those  strains  which  are  not  suited  to  the  new  locality. 

Although  these  tests  are  regarded  by  the  experimenters  as  unfin¬ 
ished  and  were  made  with  a  limited  number  of  varieties  and  in  one 
locality  only,  they  appear  to  indicate  (1)  that  the  selection  of  seed 
ears  of  a  length  less  than  normal  for  a  given  variety  or  locality  will 
reduce  the  yield  and  shorten  the  length  of  the  ear;  (2)  that  tapering 
ears  produce  slightly  higher  average  yields  than  cylindrical  ears; 
(3)  that  continuous  selection  of  ears  having  1  to  1J  inches  of  bare 
cob  at  the  tip  will  increase  the  average  amount  of  bare  cob  and 
decrease  the  yield  of  shelled  corn;  (4)  that  crease-dented  ears  are 
superior  to  rough-dented  ears;  (5)  that  weight  of  seed  ears  is  an 
important  factor  in  rate  of  yield;  (6)  that  seed  should  be  selected 
from  an  environment  slightly  less  favorable  than  that  in  which  it 
is  to  be  grown;  (7)  that  the  germination  test  is  not  an  index  of 
hereditary  merit;  and  (8)  that  introduced  varieties  should  be 
adjusted  to  local  conditions  by  careful  and  continued  selection. 

SEED  DISINFECTION  AND  CROP  PRODUCTIONS 

As  H.  L.  Bolley  states  in  a  recent  bulletin  of  the  North  Dakota 
station — 

It  is  now  a  well-known  fact  that  many  very  destructive  diseases  of  farm  crops  are 
introduced  by  way  of  the  seed.  It  is  also  a  well-understood  fact  that  there  are  various 
methods  of  treating  the  seed  grain,  which  more  or  less  successfully  control  the  action 
of  any  diseases  which  are  introduced  by  way  of  the  seed. 

Professor  Bolley  describes  the  general  characteristics  of  a  few  of 
the  more  important  diseases  of  wheat,  oats,  and  other  cereals  (includ¬ 
ing  flax)  to  which  he  has  given  particular  attention,  and  gives  a 
simple  statement  of  the  best  methods  and  appliances  now  known 
for  the  prevention  or  control  of  seed-borne  diseases.  He  shows 
that  “the  essential  work  involved  is  to  treat  the  seed  grain  so  as  to 
destroy  the  vitality  of  the  spores  or  filaments  of  the  .various  parasitic 
plants  which  cling  as  dust  on  the  exterior  or  within  the  covering  of  the 
seed  coats,  without  injury  to  the  germination  powers  of  the  grain 

®  Compiled  from  North  Dakota  Sta.  Bui.  87. 

419 


16 


EXPERIMENT  STATION  WORK,  LIX. 


and  to  indicate  that  this  can  be  successfully  done  in  various  ways 
and  with  various  substances  as  disinfecting  agents.” 

Ilis  recommendations  as  applied  especially  to  North  Dakota  con¬ 
ditions  are,  in  brief,  as  follows: 

For  stinking  smut  of  wheat. — (1)  Use  formaldehyde  at  the  rate  of  1  pound  (1G 
ounces  avoirdupois)  to  each  45  gallons  of  water.  (2)  Clean  and  grade  the  wheat  so 
as  to  remove  the  smut  balls  and  light-weight  kernels.  A  powerful  nearly  vertical 
wind  blast  is  best  for  this  purpose.  (3)  Wet  the  grain  in  any  manner  most  convenient 
to  the  operator,  by  dipping  machines,  sprinkling  and  shoveling,  or  by  means  of  a 
powerful  misty  spray  while  the  grain  is  being  rapidly  hoed,  raked,  or  shoveled  over. 
The  essential  feature  of  the  work  is  that  each  and  every  grain  shall  be  evenly  moist 
over  its  entire  exterior.  (4)  Do  not  use  any  more  of  the  solution  than  necessary  to 
accomplish  the  even  moistening  recommended.  In  any  case  three-fourths  gallon 
to  1  gallon  of  solution  is  a  fair  estimate  for  use  upon  each  bushel  of  dry  wheat.  (5) 
Sow  the  grain  as  soon  after  treatment  as  possible,  while  yet  damp  and  swollen;  the 
yield  will  be  better  and  the  treatment  more  certain  of  complete  prevention  of  smut 
and  other  diseases.  (6)  It  is  usually  convenient  to  treat  in  the  morning  for  after¬ 
noon  sowing  and  in  the  afternoon  for  morning  sowing,  though  in  the  larger  farms 
the  treatment  goes  on  continuously  and  the  sowing  continuously,  the  grain  being 
taken  direct  from  the  large  smut  mills  to  the  grain  drills.  (7)  Set  the  drill  to  sow 
the  proper  amount  of  swollen  grain.  This  amount  can  readily  be  ascertained  by 
experiment  in  a  few  rounds  of  the  drill  and  by  also  taking  note  of  the  amount  of  original 
dry  grain  and  ascertaining  what  the  increased  measure  is  by  swelling.  Ordinarily 
if  sown  at  once  the  drill  should  be  set  to  sow  1^  bushels  of  wheat  if  it  is  desired  that 
it  should  actually  carry  the  number  of  seeds  per  acre  represented  by  1^  bushels  of 
dry  grain.  However,  each  individual  method  of  treatment  will  cause  the  amount  of 
swelling  to  vary  somewhat,  and  different  drills  work  somewhat  differently  with  wet 
grain.  (8)  People  who  do  not  feel  sure  that  it  pays  to  disinfect  seed  wheat  or  any 
other  seed  grain  should  try  an  untreated  strip  alongside  of  the  treated  field. 

Loose  smut  of  wheat  and  barley.— The  formaldehyde  treatment  as  given  for  stink¬ 
ing  smut  of  wheat,  though  beneficial  in  the  treatment  of  loose  smut  of  wheat  and 
barley,  is  not  wholly  effective  against  these.  Those  who  wish  as  nearly  as  possible 
to  prevent  these  diseases  should  resort  to  the  development  of  the  seed  plat,  upon 
which  sufficient  seed  may  be  raised  comparatively  free  from  these  diseases  to  be 
used  for  the  general  wheat  or  barley  crop.  The  seed  for  this  plat  should  be  treated 
as  recommended  in  the  modified  liot-water  treatment. 

This  treatment  consists  of  soaking  the  seed  for  5  to  7  hours  in  cold  water,  followed 
by  immersion  in  water  at  129^°  F.  for  10  minutes  in  case  of  wheat,  and  in  cold 
water  for  5  to  7  hours  and  in  water  at  125^°  for  15  minutes  in  case  of  barley. 

Locate  the  seed  plat  as  distant  as  possible  from  general  field  crops  of  similar  grain 
and  upon  land  not  recently  cropped  to  that  grain.  Thrash  the  grain  in  a  clean 
machine  and  store  in  a  clean  bin  or  clean  bags.  As  the  loose  smuts  of  barley  and 
wheat  show  their  black  heads  early,  before  most  of  the  other  heads  form,  it  is  easy 
to  go  through  the  field  and  pull  up  the  stools  thus  attacked.  They  are  quite  as  easy 
to  find  as  mustard  blossoms.  If  any  heads  develop  in  the  seed  plat,  these  should  be 
pulled,  bagged,  and  burned  before  the  smut  begins  to  blow  about.  Cooperative 
work  by  the  farmers  of  a  given  neighborhood  will  be  essential  in  order  to  fully  rid 
the  lands  of  these  types  of  smuts. 

Corn  smut. — This  is  a  type  of  smut  that  accumulates  in  the  soil  with  considerable 
rapidity  as  crop  of  corn  follows  corn  in  the  neighborhood.  The  spores  blow  from 
stalk  to  stalk  and  from  the  wind-blown  spores  of  old  smut  masses  of  the  previous  year. 

419 


EXPERIMENT  STATION  WORK,  LIX. 


17 


The  preferable  method  of  controlling  this  disease  is  by  cutting  the  smut  masses  while 
they  are  young  and  collecting  and  burning  them  before  the  spores  can  be  distributed. 

Oat  smut. — (1)  Use  the  formaldehyde  solution  in  the  same  strength  as  recommended 
for  wheat,  and  by  any  of  the  methods  of  wetting  the  seed  found  to  be  most  convenient. 
When  properly  handled  some  of  the  smut  mills  or  dipping  machines  are  very  efficient. 
(2)  Grade  the  oats  thoroughly  so  as  to  blow  out  all  smut  masses  and  light-weight 
grains.  (3)  Wet  the  grain  so  thoroughly  that  the  solution  may  gain  access  to  the 
inside  of  the  chaff  scales.  The  oats  should  remain  piled  from  two  to  three  hours, 
to  allow  the  moisture  to  penetrate.  The  writer  prefers  to  wet  the  oats  sufficiently 
to  cause  them  to  swell,  and  then  at  the  end  of  two  hours  follow  this  by  a  second  wetting, 
a  process  which  insures  effective  moistening  of  all  of  the  spores.  It  is  to  be  remembered 
that  formaldehyde  fumes  do  not  kill  smut  spores  unless  the  smut  spores  are  wet. 

Each  man’s  treatment  will  cause  a  different  amount  of  swelling  of  the  grain,  and 
the  drill  should  be  set  accordingly  to  cause  the  proper  amount  of  seeding.  If  the 
work  is  well  done,  2  bushels  of  dry  grain  will  equal  approximately  2£  bushels  after 
the  treatment.  Do  not  allow  the  grain  to  dry  out  before  sowing. 

Millet  smut. — Use  the  same  treatment  and  the  same  methods  as  with  oats. 

Flax  wilt  and  flax  canker. — (1)  Select  only  plump,  bright-colored  flaxseed  for  sow¬ 
ing  purposes.  (2)  Fan  and  grade  this  seed  until  all  light-weight  seeds  and  all  bits 
of  chaff  and  straw  and  dirt  particles  are  removed,  for  these  carry  the  disease  internally 
and  can  not  be  sufficiently  wet  to  destroy  the  parasites.  (3)  Place  a  measured  quan¬ 
tity  of  seed,  say  5,  10,  15,  20,  or  30  bushels,  upon  a  canvas  or  tight  floor.  (4)  Use 
formaldehyde  solution  at  the  rate  of  1  pound  to  40  gallons  of  water.  (5)  While  one 
person  rapidly  rakes  or  shovels  over  the  grain,  put  on  the  solution  in  the  form  of  a  fine 
misty  spray.  A  compressed-air  sprayer  is  essential  for  this  work.  Dry  flaxseed, 
when  treated  in  this  manner,  will  easily  absorb  one-half  a  gallon  of  solution  for  each 
measured  bushel.  Indeed,  if  the  shoveling  and  raking  is  sufficient,  two-thirds  of  a 
gallon  may  be  used  without  causing 'matting.  When  the  work  is  sufficiently  done 
the  seed  will  look  befogged  or  thoroughly  moist.  (6)  Leave  the  grain  piled,  covered 
by  blankets  or  canvas,  from  two  to  three  hours,  after  which  it  may  be  shoveled  over 
and  then  it  is  ready  for  seeding.  (7)  Seed  such  treated  flax  upon  land  that  has  not 
previously  grown  flax  for  a  number  of  years,  preferably  five  or  six  years.  (8)  Cease 
sowing  flax  consecutively  upon  the  same  land.  (9)  Introduce  as  long  a  series  of  rota¬ 
tions  as  possible,  especially  ones  which  include  a  cultivated  crop,  such  as  corn.  This 
care  with  regard  to  rotation  with  reference  to  the  flax  crop  is  essential,  because  the 
flax  diseases  are  of  such  nature  that  they  propagate  and  spread  through  the  soil  after 
the  manner  characteristic  of  potato  scab.  These  diseases  especially  develop  upon 
the  masses  of  flax  stubble  and  roots.  The  aim  of  the  rotation  is  to  allow  this  food 
material  for  the  flax  parasites  to  decompose  and  disappear.  The  chief  aim  of  the 
treatment  is  to  prevent  the  introduction  by  way  of  the  seed  of  new  points  of  infection 
in  the  soil.  It  does  this  quite  effectively  and  at  the  same  time  insures  the  treated 
crop  against  disease,  provided  the  soil  upon  which  the  seeds  are  sown  is  not  already 
diseased.  (10)  Those  who  have  their  entire  farm  flax-sick  should  practice  growing 
their  own  seed,  for  eventually  if  what  they  save  from  such  flax-sick  soil  is  properly 
graded  the  seed  thus  obtained  will  each  year  grow  more  and  more  resistant  to  wilt. 

Yeasts,  molds,  blights,  rots,  etc. — There  is  no  class  of  garden,  forage,  or  cereal  crops 
the  seed  of  which  may  not  be  injured  at  germination  time  by  the  presence  of  ordinary 
molds,  bacteria,  and  ordinary  yeast  fungi.  Grass  seeds,  clovers,  alfalfa,  corn,  onions, 
beets,  etc.,  are  all  benefited  by  being  disinfected  before  planting.  The  formaldehyde 
solution  as  recommended  for  wheat  and  oats  is  the  most  efficient  seed  disinfectant 
known  for  such  purposes.  Seed  corn,  especially,  is  highly  benefited  by  the  treatment. 
Ordinary  yeasts,  molds,  and  bacteria  which  are  in  no  way  capable  of  producing  a  dis¬ 
ease  of  the  corn  plant  itself  produce  great  harm  to  the  seedling  by  bringing  about 
419 


18 


EXPERIMENT  STATION  WORK,  LIX. 


molding  and  fermentation  of  the  food  materials  stored  in  the  mother  seed.  If  the 
growth  season  is  cold  and  backward,  disinfected  seed  does  not  ferment  and  decay  as 
rapidly  as  seed  which  has  not  been  properly  treated.  On  the  untreated  seed  all  sorts 
of  molds  and  decay  fungi  at  once  start  up  fermentation  of  the  stored  food  materials  and 
the  products  formed  are  poisonous  to  the  young  plant. 

Root-rots  and  blights  of  wheat. — New  studies  conducted  by  this  Department  have 
demonstrated  the  fact  that  the  wheat  crops  are  quite  commonly  attacked  by  three  or 
four  types  of  minute  fungi  not  heretofore  recognized  as  definite  wheat  parasites.  These 
parasites  not  only  attack  the  wheat  heads  and  grains  but  gain  entrance  to  the  interior 
of  the  grain  and  bring  about  blighting  and  shriveling,  and  also  live  over  in  the  soil 
after  the  manner  characteristic  of  flax-wilt  and  flax-canker  fungi.  It  is  therefore 
important  that  seed  treatment  and  rotation  of  crops  be  followed  for  exactly  the  same 
reason  as  given  for  the  prevention  of  the  diseases  of  flax.  As  the  wheat  crop  is  much 
more  general  in  its  distribution  than  flax,  it  will  be  more  difficult  to  gain  as  definite 
results. 

Treatment. — (1)  Obtain  home-grown  seed  of  pure  variety.  (2)  Select  the  brightest, 
plumpest,  and  heaviest  type  of  berry  possible.  (3)  Grade  this  grain  by  means  of  a 
heavy  wind  blast,  preferably  vertical,  in  such  manner  as  to  eliminate  the  light-weight 
shriveled  kernels.  Treat  the  seed  as  recommended  for  smuts  of  wheat,  either  by  the 
formaldehyde  method  or  the  modified  hot- water  method.  As  these  diseases  of  wheat 
often  attack  the  grains  internally,  it  is  possible  that  some  new  method  of  seed  treatment 
will  yet  supplant  ones  now  in  common  use,  though  these  are  extremely  efficient.  (4) 
Sow  the  treated  grain  upon  soil  that  has  not  lately  been  occupied  by  wheat.  The 
rotation  should  be  of  such  nature  as  to  introduce  one  or  more  thorough  cultivations  of 
the  soil,  such  as  that  necessary  to  develop  a  proper  corn  or  potato  crop.  (5)  In  fertiliz¬ 
ing  land  which  is  to  be  sown  to  wheat,  use  thoroughly  composted  manure,  that  the 
diseases  which  are  resident  upon  the  wheat  straw  commonly  used  in  animal  bedding 
may  be  killed  by  the  composting  process. 

BLACKLEG  OF  THE  IRISH  POTATO.® 

In  a  recent  bulletin  of  the  Maine  Station  Prof.  W.  J.  Morse  gives 
an  account  of  this  disease  from  which  the  following  statement  is 
condensed : 

Blackleg  is  a  bacterial  disease  of  the  stems  and  tubers  of  the  potato, 
probably  introduced  into  Canada  from  England  and  from  there  into 
the  United  States.  It  occurs,  to  some  extent  at  least,  over  a  consid¬ 
erable  area  of  the  potato-growing  sections  in  the  eastern  United 
States  and  Canada.  A  similar  disease  is  also  found  in  England, 
Germany,  France,  and  other  parts  of  Europe.  It  has  been  reported 
from  Charleston,  S.  C.,  Norfolk,  Portsmouth,  and  several  points  on 
the  eastern  shore  of  Virginia;  Beltsville,  Md.,  Long  Island,  N.  Y., 
Gurley,  Colo.,  and  Plainesville,  Ohio.  It  is  probably  in  Oregon,  and 
is  apparently  becoming  widely  distributed  throughout  much  of  the 
potato-growing  areas  of  the  United  States. 

As  a  rule,  the  plants  first  show  signs  of  the  disease  when  they  are 
6  to  8  inches  high  and  growing  rapidly.  Very  moist,  cloudy  weather 
favors  its  progress,  resulting  in  the  early  death  of  the  young  plants 


419 


a  Compiled  from  Maine  Sta.  Bui.  174. 


EXPERIMENT  STATION  WORK,  LIX. 


19 


within  a  period  of  four  to  six  weeks,  while  dry  weather  may  check  its 
progress. 

The  attacked  plants  are  usually  unthrifty,  light  green  in  color,  or 
even  yellow,  and  undersized.  The  branches  and  leaves  have  a  ten¬ 
dency  to  grow  upward,  forming  a  rather  compact  top,  often  with  the 
young  leaves  curled  and  folded  up  along  the  midrib.  The  most 
characteristic  symptom  is  the  inky  black  discoloration  of  the  stem 
at  or  below  the  surface  of  the  ground.  This  discoloration  often 
extends  2  or  3  inches  above  the  surface,  and  the  invaded  tissues  show 
a  soft,  wet  decay  during  the  active  progress  of  the  disease.  Usually 
the  seed  tubers  attached  to  affected  stems  are  entirely  decayed  by  a 
soft  rot.  Occasionally,  when  the  disease  makes  slow  progress  on 
account  of  dry  weather,  new  shoots  may  put  out  above  the  infected 
region,  bearing  many  small  potatoes,  even  to  the  extent  of  producing 
small  green  tubers  upon  the  stem  above  the  ground.  Infection  of  the 
growing  plants  always  begins  below  the  ground,  usually  at  the  junc¬ 
tion  of  the  stem  with  the  diseased  seed  piece.  The  germs  of  the  dis¬ 
ease  are  capable  of  causing  a  rapid  decay  of  the  young  tubers,  and 
these  are  sometimes  attacked  also. 

It  seems  that  the  blackleg  is  largely  distributed  by  means  of  germs 
in  the  wounds,  cracks,  and  decayed  areas  of  the  seed  tubers.  The 
propagation  and  spread  of  the  disease  can  probably  be  controlled  by 
the  selection  of  seed  from  fields  free  from  the  disease,  the  rejection  of 
all  seed  tubers  which  have  wounds,  cracks,  or  decayed  areas,  and  by 
treating  the  remainder  with  corrosive  sublimate  or  formaldehyde 
solution,  or  with  formaldehyde  gas,  as  is  done  for  potato  scab. 

It  is  not  known  whether  the  disease  germs  will  remain  alive  in  the 
soil  to  infect  future  crops  of  potatoes  or  not,  but  as  a  precautionary 
measure  the  land  on  which  the  disease  occurs  should  be  kept  in  grass, 
clover,  or  cereals  for  as  long  a  time  as  possible  before  planting  with 
potatoes  again. 

In  no  region  has  this  disease  done  much  damage  as  yet,  although  it 
may  become  a  serious  pest  in  some  sections,  and  potato  growers 
should  therefore  be  on  their  guard  against  its  introduction  into  new 
areas  or  its  further  dissemination  in  regions  already  known  to  be 
infected. 

PROGRESS  IN  HORSE  BREEDING.® 


No  great  progress  can  be  made  in  breeding  animals  of  any  species 
so  long  as  the  breeding  stock  consists  ctf  unsound  individuals  or  is  of 
unknown  breeding.  The  country  is  overrun  with  grade  and  scrub 
stock  of  all  kinds,  and  in  the  breeding  of  horses  there  has  been  much 


a  Compiled  from  Wisconsin  Sta.  Buis.  127,  141,  155,  158,  169,  186,  188;  U.  S.  Dept. 
Agr.,  Bur.  Anim.  Indus.  Circs.  124,  137. 

419 


20 


EXPERIMENT  STATION  WORK,  LIX. 


fraud  concerning  age,  quality,  and  breeding  of  sires  allowed  to  stand 
for  public  service.  A  definite  plan  for  breeding  operations  has  been 
lacking.  Some  farmers  have  attempted  to  improve  their  stock  by 
grading  up  with  pure-bred  sires,  but  oftentimes  unsuitable  types 
have  been  used  and  all  sorts  of  crosses  have  been  made.  The  result 
has  been  unsatisfactory. 

The  advantages  of  pure-bred  stock  from  a  business  point  of  view 
are  discussed  by  Dr.  A.  S.  Alexander,  of  the  Wisconsin  Station,  as 
follows : 

As  a  business  proposition,  it  pays  best  to  breed  mares  to  pure-bred  stallions,  although 
the  service  fees  of  such  horses  are  higher  than  those  of  the  grade  or  mongrel  and  scrub. 
The  fees  of  the  latter  are  $5  to  $10  less  at  the  time  of  service,  but  when  the  colt  reaches 
market  age  the  saving  is  lost.  There  is  at  that  time  a  difference  of  at  least  $100  in 
value  in  favor  of  the  colt  from  the  pure-bred  sire,  so  that  the  higher  service  fee  has 
proved  a  profitable  investment.  Then,  too,  there  is  a  ready,  appreciative  outside 
market  for  the  good  grade  colt,  while  the  scrub  goes  to  the  local  buyer  at  low  figures 
and  there  is  little,  if  any,  demand  for  such  horses.  *  *  * 

While  some  farmers  are  beginning  to  appreciate  the  importance  of  using  sound,  pure¬ 
bred  stallions,  the  equal  importance  of  using  sound  mares  is  not  yet  generally  under¬ 
stood.  When  a  mare  by  reason  of  unsoundness  no  longer  is  fit  for  anything  else  she  often 
is  set  aside  for  breeding  purposes,  and  so  long  as  this  absurd  and  ruinous  policy  persists 
the  penalty  will  be  paid  in  the  prevalence  of  unsound  horses  on  our  farms.  For  cor¬ 
roboration  of  what  has  been  asserted  here,  one  has  only  to  examine  the  brood  mares 
on  a  number  of  farms  in  different  districts  of  the  State.  The  unsound  mares  will  be 
found  numerous  and  many  of  their  adult  offspring  are  similarly  affected.  *  *  * 

The  success  achieved  in  the  breeding  of  Clydesdale  horses  in  Canada  serves  as  a 
good  example  of  what  can  be  accomplished  by  persistency  and  expert  selection.  The 
Scottish  element  of  the  Dominion’s  population  has  been  partial  to  the  Clydesdale  breed 
and  conversant  with  its  good  qualities  and  utility,  hence  imported  Clydesdale  stal¬ 
lions  of  the  best  character  have  been  largely  employed  in  the  breeding  operations  of 
that  country  since  the  year  1842.  Practically  speaking,  no  alien  crosses  have  been 
made,  and  the  average  farmer  has  been  capable  of  selecting  suitable  mares  and  of 
adequately  developing  their  progeny.  The  result  is  that  Canada  has  but  one  type  of 
draft  horses,  and  it  is  a  good  one,  showing,  to  a  high  degree  of  excellence,  all  of  the 
breed  characteristics  of  the  pure-bred  Clydesdale.  *  *  *  The  same  thing  is  true, 
to  an  even  greater  degree,  in  Scotland,  where  the  Clydesdale  breed  predominates  and 
has  been  developed  to  a  high  state  of  purity,  breed  character,  and  utility.  On  the 
contrary,  if  we  examine  the  average  team  horses  of  Milwaukee  or  Chicago,  we  shall  see 
every  possible  type  and  character  represented  and  plain  evidences  of  mixed  breed¬ 
ing,  careless  selection,  and  incomplete  nutrition. 

By  gradual  processes  the  farming  communities  of  European  coun¬ 
tries  have  replaced  their  scrub  stallions  with  pure-bred  sires.  They 
have  learned  by  experience  that  the  greatest  profits  are  to  be  gained 
by  the  production  of  pure-bred  and  high-grade  stock,  and  in  many 
breeding  centers  they  will  not  keep  or  patronize  a  nonregistered  sire. 
The  various  governments  and  national  and  local  breeding  associa¬ 
tions  have  aided  greatly  in  the  work  of  eliminating  unsound,  unsuit¬ 
able  breeding  stock.  In  breeding  centers  registered  mares  are  to  be 

419 


21 


EXPERIMENT  STATION  WORK,  LIX. 

found  at  work  in  the  fields  that  are  mated  with  inspected,  pure-bred 
stallions.  In  Great  Britain  practically  all  farmers  recognize  the  impor¬ 
tance  of  using  pure-bred  sires,  and  only  such  are  used  in  various  dis¬ 
tricts  whence  come  the  many  well-known  British  breeds  of  horses.  In 
Scotland  only  one  nonregistered  stallion  has  been  reported  as  being 
used  for  public  service  in  that  country  since  1900. 

The  French  Government  for  over  LOO  years  has  maintained  stables  of  carefully 
selected,  sound,  pure-bred  stallions  for  breeding  purposes. 

The  best  stallions  in  France  are  annually  chosen  for  use  in  the  studs,  and  since 
1885,  when  a  government  decree  to  that  effect  was  promulgated,  all  stallions  not 
coming  within  special  classes  have  been  excluded  from  public  service.  The  classes 
referred  to  are  selected  by  government  veterinarians  who  inspect  all  horses  and  grade 
them  as  follows:  “Subsidized”  class,  comprising  stallions  of  a  certain  standard  and 
for  each  of  which  a  cash  bonus  of  from  $60  to  $100  per  year  is  paid  to  the  owner  to 
keep  the  animal  in  the  country  for  use  by  owners  of  mares;  “authorized”  class,  com¬ 
prising  horses  of  slightly  lower  quality  that  are  authorized,  after  passing  inspection, 
by  a  card  certifying  them  as  recommended  by  the  Government  for  use  as  sires; 
“approved”  class,  comprising  a  few  horses  permitted  to  stand  for  service,  but  not 
granted  a  bonus  or  recommendation  card. 

In  Belgium  the  Government  has,  since  1850,  maintained  a  great  horse-breeding 
establishment  and  promotes  the  breeding  of  pure-bred  Belgian  draft  horses  (Le  Cheval 
de  trait  Beige)  by  an  annual  grant  of  $5,000  to  the  official  draft  horse  registration 
society,  and  an  annual  appropriation  of  $70,000  to  encourage  the  horse  breeding  of  the 
country.  Liberal  prizes  are  awarded  to  mares  and  foals  at  shows  throughout  the 
country;  stallions  are  officially  examined  by  government  experts;  and  both  approved 
stallions  and  mares  are  granted  “maintenance”  bounties  to  retain  them  in  Belgium. 
Under  such  auspices  horse  breeding  is  making  wonderful  progress  and  only  pure-bred 
stallions  are  in  use  for  service. 

In  Germany  government  supervision  of  horse  breeding  has  obtained  for  centuries 
and  to-day  is  similar  to  that  in  vogue  in  Belgium,  it  having  been  required  by  law 
“that  no  permits  should  be  issued  authorizing  the  use  of  stallions,  unless  they  passed 
a  satisfactory  government  inspection.  ”  At  the  present  time  both  the  Government 
and  agricultural  societies  promote  intelligent  horse  breeding.  Prizes  are  awarded 
for  animals  of  special  merit,  and  such  animals  must  remain  in  the  country  for  a  speci¬ 
fied  term.  First  prizes  are  awarded  only  to  mature  horses  and  mares  that  have  shown 
merit  as  breeders.  Stallion  shows  have  long  been  held  at  Aurich  in  East  Friesland, 
where  the  horses  are  brought  annually  for  inspection  and  approval.  Prizes  for  brood 
mares  are  also  awarded  by  the  Government.  Somewhat  similar  supervision  of  horse- 
breeding  matters  is  undertaken  by  the  Government  of  Austria  and  large  sums  of 
money  are  annually  devoted  to  the  encouragement  of  the  breeding  industry. 

In  Austria  there  are  two  state  studs  and  several  stallion  depots 
maintained  by  the  Government,  and  about  $1,000,000  is  annually 
expended  by  the  Government  in  the  encouragement  of  the  horse- 
breeding  industry. 

The  points  required  by  the  standard  breeding  associations  often¬ 
times  have  nothing  to  do  with  the  utility  of  the  animal.  In  order 
to  break  away  from  some  of  these  artificial  requirements  and  in  order 
to  preserve  and  further  improve  some  of  the  better  native  types  of 
horses,  the  Department  of  Agriculture  has  undertaken  cooperative 

419 


22 


EXPERIMENT  STATION  WORK,  LIX. 


experiments  with  some  of  the  state  stations,  which  promise  to  be  of 
value  to  the  American  stockman.  For  several  years  experiments 
have  been  under  way  at  the  Colorado  Station  in  breeding  American 
carriage  horses.  At  the  Iowa  Station  an  experiment  is  in  progress 
to  develop  an  American  type  of  draft  horse.  In  Vermont  a  farm  of 
400  acres  is  devoted  exclusively  to  cooperative  work  in  breeding 
horses  with  Morgan  blood,  preserving  the  type  and  increasing  the 
size.  In  this  cooperative  work  of  the  Department  the  individuality 
of  the  horse  is  the  point  given  greatest  weight  in  his  selection,  and 
strict  selection  to  type  is  the  policy  in  view.  Wherever  possible 
inheritance  of  type  has  been  combined  with  the  selection  of  type  in 
the  individual. 

That  there  is  a  growing  demand  for  American  bred  horses  is 
shown  by  the  constantly  growing  demand,  notwithstanding  the  con¬ 
tinual  rise  in  price.  To  meet  this  demand  Doctor  Alexander  advo¬ 
cates  a  campaign  for  better  breeding  which  involves  the  following: 

Grading  up  with  sound  muscular  sires;  continuous  use  of  pure-bred  stallions  of  a 
chosen  breed;  use  of  sound  stallions  and  mares  only;  proper  feeding  and  care  of  the 
mare  and  foal;  working  of  stallions  regularly;  home  production  of  pure-bred  stallions 
to  replace  grades,  mongrels,  and  scrubs  used  at  present;  use  of  grade  horses  to  replace 
scrub  horses  in  farm  teams;  organization  of  community  associations  for  promoting 
horse  breeding;  and  the  encouragement  of  the  industry  by  prizes  at  county  fairs  for 
pure-bred  stallions  and  mares  and  the  progeny  of  these  animals. 

SWEET  POTATOES  AND  THEIR  PREPARATION  FOR  THE  TABLE.® 

Various  questions  which  have  to  do  with  sweet  potatoes  have  been 
studied  at  agricultural  experiment  stations  in  States  where  this  crop 
is  an  important  one  and  valuable  data  have  been  accumulated 
regarding  varieties,  methods  of  cultivation,  the  importance  of  sweet 
potatoes  as  food  for  man  and  domestic  animals,  and  their  use  for 
starch  making  and  other  purposes. 

The  food  value  of  the  sweet  potato  has  received  attention  in  con¬ 
nection  with  the  nutrition  investigations  of  the  Office  of  Experiment 
Stations,  and  data  regarding  the  nutritive  value,  digestibility,  and 
other  topics  have  been  discussed  in  comparison  with  similar  food 
products  in  a  Farmers’  Bulletin  b  dealing  with  potatoes  and  other 
root  crops  used  as  food.  In  a  Department  publication0  dealing  with 
the  general  question  of  the  sweet-potato  industry,  information  was 
summarized  regarding  different  methods  of  preparing  this  vegetable 
for  the  table. 

As  regards  its  general  composition,  the  sweet  potato  differs  from 
the  ordinary  white  or  Irish  potato  chiefly  in  possessing  a  little  less 

a  Compiled  from  Alabama  Tuskegee  Sta.  Bui.  17;  South  Carolina  Sta.  Bui.  146. 

&U.  S.  Dept.  Agr.,  Farmers’  Bui.  295. 

CU.  S.  Dept.  Agr.,  Farmers’  Bui.  129. 

419 


EXPERIMENT  STATION  WORK,  LIX. 


23 


water  and  protein  and  considerably  more  carbohydrates  (starches 
and  sugars).  A  more  important  difference  is  found  in  the  nature 
of  the  carbohydrates,  sweet  potatoes  containing  considerable  quan- 
tites  of  sugar  as  well  as  starch,  while  starch  is  the  characteristic  car¬ 
bohydrate  of  white  potatoes.  The  proportion  of  sugar  varies  with 
different  varieties,  the  very  sweet  sirupy  yams  being  the  more  popular 
in  certain  regions  of  the  South  and  the  drier  starchy  potatoes  in  the 
northern  markets.  The  South  Carolina  Experiment  Station  has 
recently  reported  the  results  of  extensive  work  on  the  starch  content 
of  sweet  potatoes  of  different  varieties,  and  has  shown  that  the  drier 
the  potato  the  higher  the  starch  content. 

When  sweet  potatoes  are  prepared  for  the  table  about  20  per  cent 
of  the  total  weight  is  removed  with  the  skins.  Most  cooks  are  agreed 
that  the  best  results  are  obtained  when  they  are  cooked  for  a  long 
time,  the  tubers  thus  prepared  being  sweeter  and  more  palatable 
than  those  cooked  for  a  short  period.  In  experimental  work  which 
has  been  reported  a  on  this  subject  uniform  tubers  of  medium  size 
were  baked  for  20,  40,  and  60  minutes.  Contrary  to  a  common  sup¬ 
position  that  long  baking  makes  sweet  potatoes  dry,  it  was  found 
that' those  which  were  baked  an  hour  were  in  appearance  and  to  the 
taste  moister  than  those  which  were  baked  only  20  minutes,  notwith¬ 
standing  a  greater  loss  in  weight  in  baking.  Those  which  were  baked 
a  full  hour  in  the  oven  were  invariably  more  palatable  than  the 
others.  In  the  first  20  minutes  of  the  cooking  period  the  potatoes 
lost  5.3  per  cent  in  weight,  in  the  second  20  minutes  8.4  per  cent, 
and  in  the  third  20  minutes  11.4  per  cent. 

The  Tuskegee  Experiment  Station  has  issued  a  bulletin,  of  which 
G.  W.  Carver  is  the  author,  which  summarizes  data  regarding  the 
cultivation  and  uses  of  sweet  potatoes  and  includes  a  collection  of 
recipes  for  preparing  them  for  the  table.  In  most  cases  the  recipes 
deal  with  methods  of  serving  the  sweet  potato  as  a  vegetable,  though 
several  are  given  for  dishes  in  which  it  is  combined  with  meat. 
Several  of  the  recipes  which  have  to  do  with  the  preparation  of 
desserts  with  sweet  potatoes  are  given  below,  as  perhaps  such  uses 
of  sweet  potatoes  are  less  generally  known  than  the  others. 

SWEET-POTATO  PIE. 

For  sweet-potato  pie  the  sweet  potato  should  be  boiled  in  the  skin. 
When  tender  the  skin  should  be  removed,  the  potatoes  mashed  and 
beaten  until  light.  To  each  cup  of  potato  add  J  cup  of  milk,  J  cup 
of  cream,  2  well-beaten  eggs,  J  teacup  of  sugar  (or  a  smaller  quantity 
if  the  potatoes  are  very  sweet),  and  season  with  cinnamon  and  ginger, 
or  other  spices,  to  taste.  Bake  with  a  bottom  crust  only.  This 
quantity  is  sufficient  for  2  or  3  pies. 


419 


S.  Dept.  Agr.,  Farmers’  Bui.  129. 


24 


EXPERIMENT  STATION  WORK,  LIX. 


A  pie  may  also  be  made  with  sliced  sweet  potatoes  which  are  par¬ 
boiled  until  two-thirds  done  and  then  sliced  lengthwise  very  thin 
after  removing  the  skins.  The  sliced  potatoes  should  be  placed  in  a 
deep  layer  in  a  dish  lined  with  pie  crust  and  sprinkled  with  ground 
allspice  and  a  little  ginger,  cloves,  and  nutmeg.  Before  adding  the 
top  crust  small  pieces  of  butter  should  be  scattered  over  the  potatoes. 
A  teacupful  of  sugar,  J  teacupful  of  molasses,  and  4  pint  of  cream 
should  be  poured  over  the  pie,  small  lumps  of  butter  scattered  over 
the  top,  and  the  whole  dusted  sparingly  with  flour.  Then  cover 
with  hot  water  and  put  on  the  upper  crust  and  bake  in  a  moderate 
oven.  This  pie  may  be  served  hot,  with  or  without  sauce. 

• 

SWEET-POTATO  COBBLER. 

For  sweet  potato  cobbler,  prepare  the  mashed  beaten  sweet  potatoes 
as  for  sweet-potato  pie  and  fill  a  dish  with  alternate  layers  of  biscuit 
dough  or  some  similar  crust  and  sweet  potato.  The  dough  should 
be  rolled  out  quite  thin  and  spread  with  the  sweet-potato  mixture 
in  layers  about  \  inch  thick.  Add  to  each  layer  just  enough  water 
to  give  the  crust  when  cooked  the  consistency  of  peach  or  other 
fruit  cobbler  crust.  Bake  until  thoroughly  done  and  serve  hot  with 
drawn  butter  or  hard  sauce. 

BAKED  SWEET  POTATO  AND  APPLES. 

The  recipe  for  sweet  potatoes  baked  with  apples  is  as  follows: 
Wash  4  medium-sized  potatoes,  peel,  and  cut  the  potatoes  in  slices 
about  }  inch  thick;  pare  and  slice  the  same  number  of  apples  in  the 
same  way.  Put  the  sweet  potatoes  and  apples  in  a  baking  dish  in 
alternate  layers;  sprinkle  1J  cups  of  sugar  over  the  top,  scatter  \ 
cup  of  butter  also  over  the  top;  add  f  pint  of  hot  water;  bake  slowly 
for  1  hour;  serve  steaming  hot. 

In  some  parts  of  Asia  sweet  potatoes  are  preserved  in  sugar  in 
much  the  same  way  as  fruits  in  the  United  States,  and  recipes  are 
occasionally  found  in  cookery  books  for  such  preserves,  lemon  and 
ginger  or  some  similar  material  being  usually  employed  as  a  seasoning 
material. 


419 


o 


